Apparatus for manufacturing strip brushes

ABSTRACT

Apparatus for manufacturing strip brushes which is operable to move an elongated open-topped channel strip, a series of elongated bristles, and an elongated binding element together at a press station. The outer edge of a press wheel presses the midregions of the bristles and the binding element into the channel strip at the press station. Rows of teeth extending around the periphery of the press wheel engage the bristles adjacent opposite sides of the channel strip to maintain proper bristle alignment as they are pressed into the channel strip. A pair of opposed clamp members spaced downstream from the press wheel clamp the sides of the channel strip toward each other to lock the bristles and binding element therein. A retainer shoe extends between the press member and the clamp members to hold the midregions of the bristles in the channel strip until they are locked therein.

United States Patent [72] Inventor Benjamin Koback 3,107,945 10/1963 Whitman etal, 300/2 Portland,0reg. 3,178,230 4/1965 Carlson et a1 300/2 {2H P 855350 Primary Examiner-Granville Y.Custer, Jr.

[22] Filed Sept. 4, 1969 A K h&H

45 Patented July 20,1971

[73] Assignee Ben-Ko-Matic Inc.

Portland, Oreg.

{54] APPARATUS FOR MANUFACTURING STRIP BRUSHES 8 Claims, 8 Drawing Figs.

[52] US. Cl 300/2 [51} Int. Cl A46d 9/00 [50] Field of Search 300/2, 21

[56] References Cited UNITED STATES PATENTS 1,871,775 8/1932 Cave 300/21 1,963,045 6/1934 Bickel 300/2 2,105,334 1/1938 Scully et a1. 300/2 2,400,809 5/1946 Cave 300/2 X ABSTRACT: Apparatus for manufacturing strip brushes which is operable to move an elongated open-topped channel strip, a series of elongated bristles, and an elongated binding element together at a press station. The outer edge of a press wheel presses the midregions of the bristles and the binding element into the channel strip at the press station. Rows of teeth extending around the periphery of the press wheel engage the bristles adjacent opposite sides of the channel strip to maintain proper bristle alignment as they are pressed into the channel strip. A pair of opposed clamp members spaced downstream from the press wheel clamp the sides of the channel strip toward each other to lock the bristles and binding element therein. A retainer shoe extends between the press member and the clamp members to hold the midregions of the bristles in the channel strip until they are locked therein.

PATENTED JUL 20 19?:

SHEET 2 OF 2 Benjamin Koback BY JNVENTOR Ko//'5(/7 S Harfwa/l APPARATUS FOR MANUFACTURING STRIP BRUSHES This invention relates to apparatus for manufacturing strip brushes.

Apparatus has been designed previously for manufacturing certain types of strip brushes, with the apparatus being operable to move an elongated open-topped channel, a series of bristles and an elongated binding element together at a press station. The bristles moved by such apparatus generally extend transversely of the channel strip with their midregions overlying the channel strip, while the binding element overlies the midregions of the bristles and extends parallel to the channel strip. Press means is provided for pressing the midregions of the bristles and the binding element into the channel strip with the end portions of the bristles then projecting outwardly from the channel. The sides of the channel strip are then clamped toward each other to lock the bristles and binding element in the channel strip. Strip brushes produced in this manner are adapted to be used in many ways, including being wound in a helix to form brooms for mechanical sweepers, and being inserted into various types of holders for other cleaning purposes.

When the bristles and the binding element are being pressed into the channel strip, some of the bristles tend to skew from their desired alignment. When this occurs, the end portions of the bristles which have skewed will extend outwardly from the channel strip with one end portion disposed at an angle pointing in one direction along the channel strip and with the other end portion disposed at an angle pointing in the opposite direction. This tends to produce brushes with uneven bristle distribution.

A general object of the invention is to provide novel bristlealigning means for brushmaking apparatus which will maintain proper alignment for bristles as they are pressed into a channel strip.

Another object is to provide such novel bristle-aligning means which is simply and economically constructed.

More specifically, an object is to provide in such brushmaking apparatus a press member having an outer edge which moves in the direction of, and at a speed coordinated with, the movement of a channel strip. The press member has a row of teeth projecting outwardly from its outer edge to form bristlereceiving pockets extending in the direction in which it is desired to align the bristles. The teeth engage the bristles adjacent opposite sides of the channel strip to maintain them in desired alignment as they are pressed into the channel strip.

Yet another object'is to provide for such apparatus novel bristle-aligning means in which the teeth are distributed in spaced-apart rows along opposite sides of the press member to provide a groove therebetween for receiving a binding element, with the groove paralleling the path of the channel strip. Wlth this construction, the bristles may be maintained in correct alignment by the teeth Md the binding element may be guided into a position overlying such bristles as they are pressed into the channel strip by the press member.

As has been mentioned previously, after the midregions of the bristles and binding element are pressed into the channel strip, the sides of the channel strip are clamped toward each other. This is accomplished by moving the channel strip through a nip formed by converging side portions of a pair of opposed spaced-apart rollers, positioned some distance downstream from the press member. Since the rollers are downstream from the press member, some means is required for holding the binding element and midregions or" the bristles within the channel strip as they are moved from the press member to the rollers.

A further object of the invention is to provide novel retainer means for holding the midregions of such bristles and binding element within a channel strip as they are moved from the press member to the rollers. The retainer means of the invention includes a foot portion which bears against the binding element and bristles and is beveled adjacent its downstream end to permit it to extend as close to the nip of the rollers as possible while still permitting the sides of the channel strip to be pressed toward each other without damaging the bristles.

Yet another object is to provide novel selectable pressure means for varying the pressure with which the foot portion of the retainer means bears against the binding element and bristies.

These and other objects and advantages will become more fully apparent as the description is read in conjunction with the drawing, wherein:

FIG. 1 is a side elevation of brushmaking apparatus as contemplated by the invention;

FIG. 2 is an enlarged view of a portion of the apparatus at the right-hand side of FIG. 1;

FIG. 3 is a view taken generally along the line 3-a 3 in FIG..

FIG. 4 is a top plan view taken generally along the line 4-4 in FIG. 2, and enlarged in scale, of a pair of clamping rollers which may be used in the apparatus;

FIG. 5 is a view similar to FIG. 4 illustrating a modified pair of clamping rollers which may be used in the apparatus;

FIG. 6 is a view taken generally along the line 6-6 in FIG. 5;

FIG. 7 is an enlarged view taken generally along the line 7-7 in FIG. I; and

FIG. 8 is a view taken generally along the line 8-8 in FIG. 7.

Referring now to the drawings, and first more particularly to FIG. 1, at 10 is indicated generally a brushmaking. machine, or apparatus. The apparatus is adapted to move an elongated open-topped channel strip, or brush base, 12, a series of elongated bristles l4, and a binding wire, or element, 16 into contact with each other at a press station indicated generally at 22. At the press station the bristles may extend transversely of the channel strip with midregions of the bristles overlying the open top of the channel strip, and the binding wire may extend parallel to the channel strip overlying the midregions of the bristles. The apparatus is adapted to press the midregions of the bristles and the binding wire into the open top of the channel strip causing the bristles to curve in a reverse bend at their midregions with the end portions of the bristles then extending normally outwardly from the channel strip. An elongated strip rush, indicated generally at 26, at the right, or downstream, end of the apparatus, thus may be formed by the apparatus.

The apparatus, as shown in FIG. 1, includes a base frame 28, on the left end of which is mounted an electric motor illustrated in dotted outline at 30. The longitudinal axis of the apparatus extends from left to right in FIG. 1 and occupies a vertical plane, which will be referred to herein as a reference plane.

A series of forming rollers 32, 34, 36, 38, are mounted on the frame and occupy a portion of the reference plane. Each roller is positioned to rotate about a substantially horizontal axis. Rollers 32, 34 are closely spaced to provide a forming nip therebetween. A drive chain 40 drivingly connects roller 32 to motor 34). Rollers 32, 34 having mating peripheral margins of such shapes that a substantially flat piece of malleable strip stock passed therethrough will be formed into a channelshaped cross section. Further explaining, the material for open-topped channel strip 12 enters the rollers at the left of FIG. I as a flat, elongated strip of metal. On passing between rollers 32, 34 it is formed into the open-topped channelshaped cross section illustrated in FIG. 3 having opposed sidewalls 12a, 12b and a bottom 12c. With roller 32 rotated under power the cannel strip is urged to move along a path in a downstream direction, to the right in FIG. 1.

The channel strip on leaving rollers 32, 34 has a tendency to curl upwardly due to the forming process. Rollers 36, 38 are positioned downstream from rollers 32, 34 to relieve this curling tendency from the channel strip so that it will move along a substantially straight .path through the apparatus. After passing rollers 36, 38 the channel strip is supported on, and moved along, the top of an I-beam 40 until it reaches press station 22.

Supported on frame 28, above the forming rollers, is a bristle tray 42. A pair of feed chains 44 (only one of which may be seen in FIG. 1) are mounted with their upper reaches projecting horizontally outwardly and to the right of tray 42 in FIG. 1. The feed chains are disposed parallel to and are laterally spaced from each other on either side of the reference plane.

The chains are provided with fingers 46 which are secured to the links in the chain and project vertically upwardly from the upper reaches of the chains. The fingers on one chain are aligned with the fingers on the other chain.

The feed chains are supported adjacent their opposite sets of ends on sprockets such as that illustrated in dashed outline at 48 in FIG. 1. Sprocket 48 is driven under power through a drive chain 50 connected to the motor, and is adapted to drive the chains with their upper reaches progressing to the right.

A collection of bristles I4 is shown adjacent the rear, or left, end of tray 42, with the bristles extending transversely of, and with their midregions occupying a portion of, the vertical reference plane passing through the longitudinal axis. When manufacturing a brush, bristles are moved forwardly from the pile and onto the rear ends of the upper reaches of the feed chains. As the chains are moved, fingers 46 work their way between adjacent bristles. The bristles, when seated on the chains, are carried along with the upwardly projecting fingers pulling the bristles forwardly and producing a substantially regular spacing therebetween. Since the chain reaches are parallel and the upwardly projecting fingers on one chain are aligned with the fingers on the other chain, the bristles are moved forwardly in an orderly manner to the press station.

Referring to FIGS. 1, 7, and 8, a bristle regulator, indicated generally at 52, is positioned above the bristle tray and the rear portions of chains 44. As is seen in FIGS. 7 and 8, the regulator includes a pair of laterally spaced, substantially parallel, elongated rod members 53, which are secured, adjacent their right set of ends in the figures, to a bar 54 extending across and secured to tray 42. Members 53 have central portions 53a, which extend parallel to and above chains 44, and left end portions 531;, which curve upwardly from the chains. A bar 55 extends between and is secured, as by welding, to end portions 53b of the rod members. A threaded rod 56 is secured to bar 55, a threaded rod 57 is secured to bar 54 and these two threaded rods are connected by a turnbuckle 58.

The bristle regulator is operable to regulate the depth of groups of bristles which may be moved onto chains 44. Adjustment of turnbuckle 58 in one direction will raise end portions 53b farther above the bed of tray 42 to permit greater numbers of bristles to pass onto chains 44 while adjustment of the turnbuckle in the opposite direction lowers end portions 53b to restrict the passage of bristles. The regulator thus is adapted to determine the density of bristles in a brush produced by the apparatus.

Mounted above chains 44 and occupying a portion of the vertical reference plane is a rotatable drum 60 upon which a supply of binding wire 16 is wound. Wire from the drum extends downwardly and under a roller, illustrated in dashed outline at 62, and thence forwardly to press station 22. The apparatus is adapted to draw wire 116 from the drum and into the press station by the use of means which will be described below.

It has been found that the best results are obtained when wire 16 is under tension. A band brake 66 is provided to act upon the axle upon which drum 60 is mounted to produce resistance to the drawing of wire l6 and tense the wire. The resistance produced by brake 66 is adjustable and a gauge 68 is provided to register the resistance to permit desired adjustment of the brake.

.loumaled on the frame beneath drum 60 is a forwardly projecting arm 70 which is mounted for swinging in a vertical plane. A disc-shaped press member 72 is journaled for rotation about a horizontal axis adjacent the forward end of arm 70. With the arm in its lowered position, as illustrated in FIG. 1, a lower peripheral portion of press member 7 2 lies within press station 22. Referring now to FIGS. 2 and 3, it will be seen that, in operation, a portion of the periphery of press member 72 rests within the open top of the channel strip as it is moved along a path through the press station.

A plurality of teeth 74 are positioned about the periphery of the disc and are disposed in a pair of rows spaced apart axially of the disc. The teeth project radially outwardly from the disc with the teeth in one row aligned with corresponding teeth in the other row to define bristle-receiving pockets 76 which extend transversely of the longitudinal axis of the apparatus, and thus in the direction in which it is desired to maintain alignment of the bristles. The space between the rows of teeth provides a groove 80 extending about the periphery of the disc which is adapted to receive and guide binding wire 16 as shown in FIG. 3. As is best seen in FIG. 3, teeth 74 have such length that with the binding wire received in the groove they project radially outwardly some distance beyond the binding wire, or element, to provide bristle-receiving pockets outwardly from the binding wire.

In operation of the apparatus thus far described, the channel strip is moved to the press station with its open top up and the bristles are moved thereto extending transversely of the path of the channel strip with their midregions overlying the channel strip. The binding wire 16 is guided into the press station by the groove in the press member, with the binding wire paralleling the path of movement of the channel strip and overlying the midregions of the bristles. A peripheral portion of press member 72 rests within the channel strip, and the bristles carried along the apparatus by feed chains 44 are received within pockets 76 on the press member. The bristles, when received in pockets 76, are engaged by teeth 74 adjacent opposite sides of the channel strip and held in their proper alignment extending transversely of the channel strip.

As the channel strip, bristles, and binding wire are moved together in a downstream direction press member 72 is caused to rotate in such a manner that its outer edge moves at a speed coordinated with the speed of the channel strip, and the midregions of the bristles and the binding wire are pressed into the channel strip by the press member. On being pressed into the channel strip the bristles assume a reverse bend configuration, as seen in FIG. 3, and opposite end portions of the bristle project substantially normally from the channel strip.

The teeth on the press member by engaging the bristles adjacent opposite sides of the channel strip maintain alignment of the bristles as they are pressed into the channel strip. This prevents them from skewing during the pressing operation to assure that end portions of the bristles in a finished brush will extend outwardly from the channel strip as desired.

Disposed downstream from the press member are a pair of opposed, spaced-apart clamp rollers, or members, 84, situated on either side of the longitudinal axis of the apparatus, see FIGS. 2 and 4. The clamp rollers are mounted for rotation about axes which are substantially normal to the path of movement for the channel strip. Each roller is drivingly connected through suitable drive means 86 and a drive chain 88 to motor 30, in such a manner that on operation of motor 30 the clamp rollers are driven.

As is best seen in FIG. 4, clamp rollers 84 provide converging surfaces which define a nip therebetween through which the channel strip may be drawn to clamp sides 12a, 12b of the channel strip toward each other to 16 the midregions of the bristles and binding wire 16 within the channel strip. Clamp rollers 84 on being rotated under power in the direction of the arrows in FIG. 4 act to draw the channel strip and binding wire locked therein in a downstream direction, and thus provide means for tensing binding wire 16 and drawing it from drum 60.

A modified form of rollers, which may be used in place of rollers 84, is illustrated at 90 in FIGS. 5 and '6. Rollers 90 have gearlike teeth 92 which project radially outwardly on the rollers. Rollers 90 are mounted and driven in the apparatus in the same manner as were previously described rollers 84. I

In operation of the apparatus with these modified rollers, the side portions 12a, 12b of the channel strip are crimped toward each other at regular intervals along the length of the strip. The crimped portions of the channel strip extend farther over the binding element to lock the element more securely in the channel strip.

A guide roller 96 is joumaled for rotation about a horizontal axis between a pair of spaced-apart vertical plates 97, 98 in a region downstream from the clamp rollers. The guide roller occupies a portion of the reference plane and acts in conjunction with plates 97, 93 to guide a section of the strip brush after it leaves the clamp rollers.

A retainer member 100 is secured to the forward end of arm 70, as is best seen in FIG. 2. The retainer member has a foot portion 100a which extends from a region adjacent the press station to a region adjacent the nip between rollers 84. The under surface of foot portion 100a is slightly grooved and narrow permitting it to press against the top of binding wire 16 and pass between the bent-up end portions of bristles 14 after they have been pressed into the channel strip. The retainer member is thus adapted to retain the midregions of the bristles and the binding wire within the channel strip, until such time as the sides of the channel strip are clamped toward each other by rollers 84. As is best seen in FIG. 4, the downstream end of foot portion 100a converges on progressing in a downstream direction, permitting it to extend as far as possible into the nip between rollers 84, while still permitting the sides of the channel strip to be clamped toward each other.

Referring again to FIG. I, a subframe 104 is joumaled for swinging movement in a vertical plane on frame 28 at points, such as that indicated at 106, on either side of the longitudinal axis of the apparatus. The subframe carries an elongated screw rod 108 which is threaded through a suitable threaded bore adjacent the upper end of the subframe.

A hand wheel 110 is secured to the upper end of rod 108. With subframe 104 in the position shown in FIG. 1, the lower end of rod 108 overlies the top of retainer member 100, and on screwing the rod downwardly it bears against the top of retainer member I00 to press it against the midregions of the bristles and the binding wire. The subframe and screw rod assembly are referred to collectively herein as selectable pressure means which is operable to vary the pressure which the retainer member exerts against the binding wire and bristles.

Since the apparatus may be used to manufacture strip brushes using various types of bristles and binding elements it has been found that different pressures on the retainer member work best for holding the different bristles and binding elements within the channel strips. To this end a pressure gauge 112 is connected to the screw rod to register the pressure with which the retainer member presses against the binding wire and bristles.

With the screw rod raised from the retainer member the subframe may be swung to the right in FIG. 1 to move it away from arm 70 and retainer member 100. Arm 70 then may be raised to lift the retainer member and press member from the channel strip, bristles and binding wire.

The operation of the apparatus described should be clear from the above. Briefly, fiat strip stock is fed between the forming rollers 32, 34 to form a channel strip which is moved into the region of the press station. Binding wire I6 is drawn into groove 80 in the press member and is guided into the channel strip at the press station. Bristles are placed on the table and spread out by hand, or other means, to bring them into proximity with the feed chains. The feed chains move forwardly with the bristles held in an orderly manner until they are engaged by teeth 74 on the press member. As the bristles are moved into the press station they are maintained in desired alignment by the teeth on the press member and the midregions of the bristles are pressed, along with the binding wire, into'the channel strip. As the channel strip, bristles and binding wire progress in a downstream direction from the press station the binding wire and midregions of the bristles are held within the channel strip by retainer member 100. On being moved farther downstream the sidewalls of the channel strip are clamped toward each other by rollers 84 to lock the midregions of the bristles and the binding wire therein. An elongated strip brush is thus formed with the bristles projecting in a desired direction normally from the channel strip and being distributed evenly therealong.

While an embodiment of the invention has been described above, it is obvious that various changes and modifications may be made without departing therefrom.

I claim and desire to secure by Letters Patent:

1. Apparatus for manufacturing strip brushes comprising means for moving an elongated open-topped channel strip in one direction along a path,

means for moving an series of elongated bristles into contact with such channel strip with such bristles extending transversely of the channel strip and with midregions of such bristles overlying the channel strip, and

a press member having an outer edge disposed adjacent the path of such channel strip, which edge is adapted to be moved in said one direction at a speed coordinated with the speed at which such channel strip is moved operable to press the midregions of such bristles into such channel strip, said member further having a plurality of teeth projecting outwardly from its said outer edge defining bristlereceiving pockets therebetween extending transversely of said edge, said teeth being operable to engage such bristles adjacent opposite sides of such channel strip and to maintain such bristles in desired alignment relative to the channel strip as they are pressed therein.

2. The apparatus of claim I, wherein said press member comprises a disc mounted for rotation about an axis which extends substantially normal to and is spaced from the path of movement for such channel strip and said disc is positioned with a segment of its periphery adjacent a portion of the path which may be traversed by the open top of such channel strip, and said teeth defining said bristle-receiving pockets are disposed about the periphery of said disc and project radially outwardly therefrom.

3. The apparatus of claim I, which further comprises a pair of opposed clamp members disposed on opposite sides of said path downstream from said press member, said clamp members having opposing surfaces which converge toward each other on progressing in a downstream direction to define a nip therebetween through which such channel strip may be moved for clamping opposed sides of the channel strip toward each other to lock the midregions of bristles therein,

a retainer member which extends along said path from a regions adjacent said press member to a region adjacent said nip, said retainer member having a downstream end portion adjacent said nip which has sides converging on progressing in a downstream direction, and being adapted to bear against the bristles to retain the midregions of such bristles within the channel strip as they are carried with the channel strip from the press member to the region adjacent the nip between the clamp members, and

selectable pressure means operable to vary the pressure which such retainer means exerts against such bristles.

4. The apparatus of claim 1, wherein said teeth are disposed in opposed spaced-apart rows extending along opposite sides of said press member and substantially parallel to the path for the channel strip, and a groove is defined between said rows of teeth extending substantially parallel to such path for receiving and guiding an elongated binding element into a region overlying such bristles with such binding element extending substantially parallel to the path for such channel strip.

5. The apparatus of claim 2, wherein said teeth are disposed in opposed rows extending about the periphery of the disc with said rows being spaced apart in a direction axially of the disc, and a groove is defined about the periphery of the disc between said rows of teeth for receiving and guiding an clongated binding element into a region overlying such bristles with such binding element substantially parallel to the path for such channel strip.

6. The apparatus of claim 5, wherein each tooth in one of said rows of teeth is substantially aligned with a corresponding tooth in the other of said rows.

other on progressing in a downstream direction to define a nip therebetween through which such channel strip may be moved for clamping opposed sides of the channel strip toward each other to lock the midregions of bristles therein, and each clamp member has thereon spaced teeth projecting outwardly toward the other clamp member for crimping side portions of such channel strip toward each other at spaced intervals along the channel strip. 

1. Apparatus for manufacturing strip brushes comprising means for moving an elongated open-topped channel strip in one direction along a path, means for moving an series of elongated bristles into contact with such channel strip with such bristles extending transversely of the channel strip and with midregions of such bristles overlying the channel strip, and a press member having an outer edge disposed adjacent the path of such channel strip, which edge is adapted to be moved in said one direction at a speed coordinated with the speed at which such channel strip is moved operable to press the midregions of such bristles into such channel strip, said member further having a plurality of teeth projecting outwardly from its said outer edge defining bristle-receiving pockets therebetween extending transversely of said edge, said teeth being operable to engage such bristles adjacent oppOsite sides of such channel strip and to maintain such bristles in desired alignment relative to the channel strip as they are pressed therein.
 2. The apparatus of claim 1, wherein said press member comprises a disc mounted for rotation about an axis which extends substantially normal to and is spaced from the path of movement for such channel strip and said disc is positioned with a segment of its periphery adjacent a portion of the path which may be traversed by the open top of such channel strip, and said teeth defining said bristle-receiving pockets are disposed about the periphery of said disc and project radially outwardly therefrom.
 3. The apparatus of claim 1, which further comprises a pair of opposed clamp members disposed on opposite sides of said path downstream from said press member, said clamp members having opposing surfaces which converge toward each other on progressing in a downstream direction to define a nip therebetween through which such channel strip may be moved for clamping opposed sides of the channel strip toward each other to lock the midregions of bristles therein, a retainer member which extends along said path from a regions adjacent said press member to a region adjacent said nip, said retainer member having a downstream end portion adjacent said nip which has sides converging on progressing in a downstream direction, and being adapted to bear against the bristles to retain the midregions of such bristles within the channel strip as they are carried with the channel strip from the press member to the region adjacent the nip between the clamp members, and selectable pressure means operable to vary the pressure which such retainer means exerts against such bristles.
 4. The apparatus of claim 1, wherein said teeth are disposed in opposed spaced-apart rows extending along opposite sides of said press member and substantially parallel to the path for the channel strip, and a groove is defined between said rows of teeth extending substantially parallel to such path for receiving and guiding an elongated binding element into a region overlying such bristles with such binding element extending substantially parallel to the path for such channel strip.
 5. The apparatus of claim 2, wherein said teeth are disposed in opposed rows extending about the periphery of the disc with said rows being spaced apart in a direction axially of the disc, and a groove is defined about the periphery of the disc between said rows of teeth for receiving and guiding an elongated binding element into a region overlying such bristles with such binding element substantially parallel to the path for such channel strip.
 6. The apparatus of claim 5, wherein each tooth in one of said rows of teeth is substantially aligned with a corresponding tooth in the other of said rows.
 7. The apparatus of claim 5, wherein said teeth have such length that with a suitable binding element received in said groove they project radially outwardly some distance beyond such binding element to provide bristle-receiving pockets outwardly from such binding element.
 8. The apparatus of claim 1, which further comprises a pair of opposed clamp members disposed on opposite sides of said path downstream from said press member, said clamp members having opposing surfaces which converge toward each other on progressing in a downstream direction to define a nip therebetween through which such channel strip may be moved for clamping opposed sides of the channel strip toward each other to lock the midregions of bristles therein, and each clamp member has thereon spaced teeth projecting outwardly toward the other clamp member for crimping side portions of such channel strip toward each other at spaced intervals along the channel strip. 